US8377748B2 - Method of manufacturing cooling fin and package substrate with cooling fin - Google Patents

Method of manufacturing cooling fin and package substrate with cooling fin Download PDF

Info

Publication number
US8377748B2
US8377748B2 US13/137,669 US201113137669A US8377748B2 US 8377748 B2 US8377748 B2 US 8377748B2 US 201113137669 A US201113137669 A US 201113137669A US 8377748 B2 US8377748 B2 US 8377748B2
Authority
US
United States
Prior art keywords
cooling fin
resin layer
cooling
support base
firing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US13/137,669
Other versions
US20110308069A1 (en
Inventor
Eung Suek Lee
Je Gwang Yoo
Chang Sup Ryu
Jun Oh Hwang
Jun Heyoung Park
Jee Soo Mok
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Samsung Electro Mechanics Co Ltd
Original Assignee
Samsung Electro Mechanics Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Samsung Electro Mechanics Co Ltd filed Critical Samsung Electro Mechanics Co Ltd
Priority to US13/137,669 priority Critical patent/US8377748B2/en
Publication of US20110308069A1 publication Critical patent/US20110308069A1/en
Application granted granted Critical
Publication of US8377748B2 publication Critical patent/US8377748B2/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • H01L23/36—Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks
    • H01L23/373—Cooling facilitated by selection of materials for the device or materials for thermal expansion adaptation, e.g. carbon
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/52—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbon, e.g. graphite
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/71—Ceramic products containing macroscopic reinforcing agents
    • C04B35/78—Ceramic products containing macroscopic reinforcing agents containing non-metallic materials
    • C04B35/80—Fibres, filaments, whiskers, platelets, or the like
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K7/00—Constructional details common to different types of electric apparatus
    • H05K7/20—Modifications to facilitate cooling, ventilating, or heating
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3217—Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/34—Non-metal oxides, non-metal mixed oxides, or salts thereof that form the non-metal oxides upon heating, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3418—Silicon oxide, silicic acids, or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/40—Metallic constituents or additives not added as binding phase
    • C04B2235/407—Copper
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/40—Metallic constituents or additives not added as binding phase
    • C04B2235/408—Noble metals
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/52—Constituents or additives characterised by their shapes
    • C04B2235/5284—Hollow fibers, e.g. nanotubes
    • C04B2235/5288—Carbon nanotubes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F21/00—Constructions of heat-exchange apparatus characterised by the selection of particular materials
    • F28F21/02—Constructions of heat-exchange apparatus characterised by the selection of particular materials of carbon, e.g. graphite
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F3/00—Plate-like or laminated elements; Assemblies of plate-like or laminated elements
    • F28F3/02—Elements or assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with recesses, with corrugations
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/10—Bump connectors; Manufacturing methods related thereto
    • H01L2224/15—Structure, shape, material or disposition of the bump connectors after the connecting process
    • H01L2224/16—Structure, shape, material or disposition of the bump connectors after the connecting process of an individual bump connector
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/4805—Shape
    • H01L2224/4809—Loop shape
    • H01L2224/48091—Arched
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/481—Disposition
    • H01L2224/48151—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/48221—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/48225—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • H01L2224/48227—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation connecting the wire to a bond pad of the item
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L24/42—Wire connectors; Manufacturing methods related thereto
    • H01L24/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L24/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/0001—Technical content checked by a classifier
    • H01L2924/00014—Technical content checked by a classifier the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/15—Details of package parts other than the semiconductor or other solid state devices to be connected
    • H01L2924/151—Die mounting substrate
    • H01L2924/153—Connection portion
    • H01L2924/1531—Connection portion the connection portion being formed only on the surface of the substrate opposite to the die mounting surface
    • H01L2924/15311—Connection portion the connection portion being formed only on the surface of the substrate opposite to the die mounting surface being a ball array, e.g. BGA
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/15—Details of package parts other than the semiconductor or other solid state devices to be connected
    • H01L2924/181—Encapsulation
    • H01L2924/1815—Shape
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/30—Technical effects
    • H01L2924/301—Electrical effects
    • H01L2924/3025—Electromagnetic shielding
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/4935—Heat exchanger or boiler making

Definitions

  • the present invention relates generally to a cooling fin and a package substrate comprising the cooling fin and a manufacturing method thereof, and, more particularly, to a cooling fin, which is excellent in cooling performance and is simply manufactured, a package substrate comprising the cooling fin, and a manufacturing method thereof
  • cooling fins which have excellent thermal conductivity, i.e., a thermal conductivity ten times or greater than that of copper.
  • a carbon nanotube is typically produced through chemical vapor deposition (CVD).
  • FIG. 1 shows a carbon nanotube 13, which is produced through chemical vapor deposition.
  • conventional carbon nanotubes 13 are produced in a manner such that nano-sized catalytic metal particles 12 are formed on a silicon substrate 11 and then the carbon nanotubes 13 grow vertically from the catalytic metal particles through a high temperature synthesis process conducted at a temperature ranging from 500° C. to 1000° C.
  • the carbon nanotubes 13 which have been produced in such a manner are attached to a target object so as to serve as cooling fins.
  • the base material from which the carbon nanotubes can be grown is disadvantageously restricted to ones which can be used at the high temperature, for example, the silicon substrate 11 , as illustrated in FIG. 1 .
  • the conventional process is disadvantageous in that there are needs for a separate metal catalyst 12 adapted to grow the carbon nanotube as well as a special container having a high hermetic performance regarding forming a nano-sized metal catalyst 12 on the silicon substrate 11 , thus increasing equipment costs.
  • the present invention has been made keeping in mind the above problems occurring in the prior art, and the present invention provides a cooling fin, which may have various configurations by incorporating a fired object containing carbon component, and a method of manufacturing the cooling fin.
  • the present invention provides a cooling fin, which may be manufactured a simple process of injecting fireable paste containing carbon nanotubes or carbon nanofiber, and a method of manufacturing the cooling fin.
  • the present invention provides a package substrate, which may be manufactured by attaching a cooling fin having an improved cooling performance to the package substrate, and a method of manufacturing the package substrate.
  • the present invention provides a package substrate, which includes a cooling fin that is configured to have a cover structure to improve a cooling performance, and which shields a printed circuit board including a semiconductor chip from an external environment in a sealing manner, thus obviating an additional resin encapsulation, and a method of manufacturing the package substrate.
  • the present invention provides a cooling fin comprising a fired object containing a carbon component.
  • the fired object may include carbon nanotubes or carbon nanofibers, and metal microparticles.
  • the present invention provides a package substrate including: a printed circuit board on which a semiconductor chip is mounted; and a cooling fin bonded to the semiconductor chip and comprising a fired object containing a carbon component.
  • the fired object may include carbon nanotubes or carbon nanofibers, and metal microparticles.
  • the cooling fin may be configured to have a cover structure so as to protect a surface of the printed circuit board including the semiconductor chip from an external environment in a sealing manner.
  • the present invention provides a method of manufacturing a cooling fin, including: preparing a mold, which comprises a support base and a resin layer formed on the support base and including on a side thereof a groove, which is configured to form a cooling fin; printing fireable paste containing a carbon component on a side of the mold that has the groove configured to form a cooling fin; removing the support base to leave a cooling object; and firing the cooling object.
  • the preparing the mold may include: placing the resin layer on a side of the support base; imprinting the resin layer with a stamp having a pattern corresponding to the groove; and removing the stamp.
  • the method may further include, after printing the fireable paste, drying the fireable paste which is printed.
  • the fireable paste may include carbon nanotubes or carbon nanofibers, metal microparticles and a binder.
  • the firing the cooling object may cause the resin layer and the binder to be eliminated.
  • the method may further include, after firing the cooling object, removing the resin layer and the binder which are not eliminated by the firing, through reactive ion etching (RIE).
  • RIE reactive ion etching
  • the present invention provides a method of manufacturing a package substrate, including: preparing a mold, which comprises a support base and a resin layer formed on the support base and including on a side thereof a groove configured to form a cooling fin; printing fireable paste containing a carbon component on a side of the mold including the groove; removing the support base to leave a cooling object; firing the cooling object to prepare a cooling fin; and bonding the cooling fin on a semiconductor chip mounted on a printed circuit board.
  • the preparing the mold may include: placing the resin layer on a side of the support base; imprinting the resin layer with a stamp having a pattern corresponding to the groove; and removing the stamp.
  • the method may further include, after printing the fireable paste, drying the fireable paste which is printed.
  • the fireable paste may include carbon nanotubes or carbon nanofibers, metal microparticles and a binder.
  • the firing the cooling object may cause the resin layer and the binder to be eliminated.
  • the method may further include, after firing the cooling object, removing the resin layer and the binder, which are not eliminated by the firing, through reactive ion etching (RIE).
  • RIE reactive ion etching
  • the cooling fin may be configured to have a cover structure so as to protect a surface of the printed circuit board including the semiconductor chip from an external environment in a sealing manner.
  • FIG. 1 is a cross-sectional view showing a carbon nanotube, which is produced through conventional chemical vapor deposition
  • FIG. 2 is a cross-sectional view showing a cooling fin according to a preferred embodiment of the present invention
  • FIG. 3 is a cross-sectional view showing a package substrate including a cooling fin, according to a preferred embodiment of the present invention
  • FIG. 4 is a cross-sectional view showing a package substrate including a cooling fin, according to another embodiment of the present invention.
  • FIGS. 5 to 9 are cross-sectional views showing a method of manufacturing a cooling fin, according to an embodiment of the present invention.
  • FIG. 2 is a cross-sectional view showing a cooling fin according to a preferred embodiment of the present invention
  • FIG. 3 is a cross-sectional view showing a package substrate including a cooling fin, according to a preferred embodiment of the present invention
  • FIG. 4 is a cross-sectional view showing a package substrate including a cooling fin, according to another embodiment of the present invention
  • FIGS. 5 to 7 are cross-sectional views showing a method of manufacturing a cooling fin, according to an embodiment of the present invention.
  • FIG. 2 a cooling fin 100 a according to an embodiment of the present invention is now described.
  • the cooling fin 100 a is distinctively comprised of a fired object containing a carbon component.
  • the fired object may include carbon nanotubes, carbon nanofibers, metal microparticles and additives.
  • the carbon nanotubes or the carbon nanofibers have electrical properties superior to other materials.
  • Table 1 represents the comparison between the physical properties of a carbon nanotube and those of other materials.
  • the carbon nanotube has electrical properties better than metal materials such as aluminum and copper, which are relatively excellent in views of electrical conductivity and specific resistance. Consequently, the cooling fin 100 a , which is comprised of a fired object containing a carbon component, has an excellent cooling performance and is thus capable of efficiently radiating heat generated in a printed circuit board.
  • the carbon nanotubes may be comprised of either or both single-walled carbon nanotubes and multi-walled carbon nanotubes, the multi-walled carbon nanotubes, which have electrical conductivity proportional to a diameter thereof, are used in this embodiment.
  • the metal microparticles which function to increase adhesiveness and electrical conductivity, may be comprised of high conductive silver (Ag) microparticles, copper (Cu) microparticles or a proper combination thereof.
  • the additive which is an element for controlling adhesiveness and printability, may be comprised of one or more selected from among organic/inorganic filler, dye, pigment, thickener, lubricant agent, defoaming agent, dispersing agent, levelling agent, flame retardant, thixotropic agent, brightener, coupling agent which includes a hydrophobic functional group capable of being coupled to resin in molecules as well as a hydrophilic functional group capable of being coupled to inorganic filler.
  • the inorganic filler which functions to lower a coefficient of thermal expansion, may include spherical/platy/amorphous silica, alumina, diatomous earth and the like.
  • the additive may include an oxide additive, such as pine tar, to eliminate oxides.
  • FIG. 4 illustrates a cooling fin 100 b having a cover configuration.
  • package substrates 150 a and 150 b which include cooling fins according to different embodiments of the present invention, are described.
  • the package substrates 150 a and 150 b which include cooling fins according to embodiments of the present invention, are characterized in that the cooling fins 100 a and 100 b , which are comprised of fired bodies containing a carbon component, are bonded on respective semiconductor chips 152 which have been mounted on printed circuit boards 152 .
  • the cooling fins 100 a and 100 b are prepared as described above, the detailed descriptions thereof are omitted for convenience of description.
  • cooling fins 100 a and 100 b are bonded on the respective semiconductor chips 152 using adhesives 153 etc.
  • the package substrate 150 a including the cooling fin is configured such that the cooling fin 100 a is directly bonded on a semiconductor chip 152 using an adhesive 153 to radiate heat generated from the semiconductor chip 152 .
  • the package substrate 150 b including the cooling fin is configured such that the cooling fin 100 b is formed into a cover shape for covering an upper surface of a printed circuit board 151 including a semiconductor chip 152 mounted on the printed circuit board 151 in a sealing manner.
  • the package substrate 150 a including the cooling fin as shown in FIG. 3 , is encapsulated in resin sealing material, such as EMC molding material, so as to protect the semiconductor chip 152 and the printed circuit board 151 from the external environment.
  • the package substrate 150 b including the cover-shaped cooling fin as shown in FIG.
  • the cooling fin 100 b seals off and shields the semiconductor chip 152 and the printed circuit board 151 from the external environment, thus obviating the necessity of providing an additional resin encapsulation and solving the deterioration of cooling efficiency due to the resin encapsulation.
  • the adoption of the cover-shaped cooling fin 100 b enables realization of the sealing function as well as of the cooling function.
  • the semiconductor chip 152 is shown mounted on the printed circuit board 151 through a wire bonding technology, it is proposed merely for illustration of an example thereof.
  • the semiconductor chip 152 may be mounted on the printed circuit board 151 through a flip-chip bonding technology, and it is applicable to various kinds of package substrates and memory chips.
  • FIGS. 5 to 9 A process of manufacturing the cooling fin according to an embodiment of the present invention is described with reference to FIGS. 5 to 9 .
  • a resin layer is first formed on one side of a support base 101 , and then the resin layer 102 is imprinted with a stamp 103 .
  • the support base 101 which is adapted to support the resin layer 102 , is preferably constructed to have at least the specific strength required to serve as supporting means.
  • the support base 101 may be comprised of a variety of metals and polymers, in particular, releasable polymers, it is comprised of a copper foil in one embodiment.
  • the resin layer 102 which is in a semicured state, may be formed on one side of the support base 101 in an appropriate way, such as spin coating, droplet dispensing and spraying.
  • any other process of forming the resin layer 102 on the support base 101 through a known way other than the above-mentioned ways should be understood to fall within the scope of the present invention.
  • the resin layer 102 may be comprised of any thermosetting resin or thermoplastic resin. More specifically, the resin layer 102 may be comprised of any of the thermosetting resins, such as vinyl ester resin, unsaturated polyester resin, maleimide resin, polycyanate resin, epoxy resin, phenol resin and vinyl benzene compound, and thermoplastic resin, such as polyetherimide resin, polyether sulfone resin and dicylcopentadiene resin.
  • thermosetting resins such as vinyl ester resin, unsaturated polyester resin, maleimide resin, polycyanate resin, epoxy resin, phenol resin and vinyl benzene compound
  • thermoplastic resin such as polyetherimide resin, polyether sulfone resin and dicylcopentadiene resin.
  • the stamp 103 is intended to imprint the resin layer 102 , which is in a semicured state, with a pattern, thereby defining desired patterned grooves 104 on the resin layer 102 which have been adapted to form the cooling fin.
  • the pattern of the stamp 103 corresponds to the grooves 104 used for forming the cooling fin.
  • the pattern of the stamp may have various shapes suitable for increasing the surface area of the cooling fin, or may have a fine structure suitable for forming the grooves 104 adapted to form a cooling fin having a respective fin thickness of several micrometers.
  • the stamp 103 is removed, thus preparing a mold 105 .
  • the resin layer 102 is provided with the cooling fin-defining grooves 104 which correspond to the pattern of the stamp 103 .
  • fireable paste 106 containing a carbon component is printed on the one surface of the support base 101 in which the cooling fin-defining grooves 104 are formed.
  • the fireable paste 106 containing a carbon component is normally comprised of a mixture of binder and powdered carbon nanotubes or carbon nanofibers powder, and may further include metal microparticles, additives and the like.
  • the fireable paste 106 may comprise about 75-85 wt % of carbon nanotubes or carbon nanofibers, about 5-10 wt % of binder and about 5 wt % of additive.
  • the details of the carbon nanotubes or carbon nanofibers, the metal microparticles and the additive has been previously described above, the description is omitted.
  • the binder which is intended to control elasticity and adhesivity of the fireable paste 106 , may be used in a varying weight composition depending on need.
  • the binder may include one or more types of thermosetting resin, such as epoxy resin, cyanic acid ester resin, bismaleimide (BMI) resin, polyimide resin, benzocyclobutene (BCB) resin and phenol resin, thermoplastic resin, such as polyurethane resin, polyamideimide resin and polyphenylene ether resin, and UV curing resin.
  • binder may be selected from the group consisting of polyethylene oxide, polypropylene carbonate and a combination thereof. This allows firing at a low temperature and easy decomposition of the binder during the firing process, thus preventing deterioration of the carbon nanotubes or carbon nanofibers and improving thermal conductivity.
  • the support base 101 is removed to leave a cooling object 107 .
  • the support base 101 when the support base 101 is embodied as a copper foil, the support base 101 may be removed using etching solution such as iron chloride (FeCl 5 ) etchant, copper chloride (CuCl 5 ), alkali etchant and hydrogen peroxide/sulfuric acid (H 2 O 2 /H 2 SO 4 ). At this time, the fireable paste 106 is not etched even by the etching solution.
  • etching solution such as iron chloride (FeCl 5 ) etchant, copper chloride (CuCl 5 ), alkali etchant and hydrogen peroxide/sulfuric acid (H 2 O 2 /H 2 SO 4 .
  • the cooling object 107 is subjected to a firing process so as to eliminate the binder and the resin layer 102 , thus preparing the cooling fin 100 a as illustrated in FIG. 2 .
  • the binder contained in the paste binds the carbon nanotubes or carbon nanofibers to each other and is then thermally decomposed and thus eliminated.
  • the resin layer 102 included in the cooling object 107 is also thermally decomposed at a temperature of 300° C. or higher, it is eliminated after the firing process.
  • the cooling fin 100 a is comprised of a fired object containing carbon nanotubes or carbon nanofibers, metal microparticles and an additive.
  • cover-shaped cooling fin 100 b is also manufactured through a process which is substantially identical to the above process used in the manufacture of the cooling fin 100 a , the description thereof is omitted.
  • a process may be further conducted such that the binder and the resin layer are eliminated using reactive ion etching (RIE) technology for improvement of the cooling performance.
  • RIE reactive ion etching
  • the reactive ion etching technology is conducted in such a manner as to react active species existing in a plasma of reactive gas with atoms on the surface of an etching target material to generate volatile reaction products, and then separate the volatile reaction products from the surface of the etching target material.
  • the reactive ion etching may be conducted through a dielectric barrier discharge (DBD) using inert gases such as argon (Ar) or helium (He).
  • the package substrates 105 a and 150 b each including the cooling fin, according to an embodiment of the present invention, is manufactured by bonding the cooling fins 100 a and 100 b , which have been prepared in the above-described way, to respective printed circuit boards 151 on which semiconductor chips 152 are mounted.
  • the process of manufacturing the package substrates is now described with reference to FIGS. 3 and 4 .
  • an adhesive 153 is applied onto a semiconductor chip 152 mounted on a printed circuit board 151 , and the cooling fin 100 a , which has been prepared through the process as shown in FIGS. 5 to 9 , is bonded to the semiconductor chip 152 via the adhesive 153 .
  • an adhesive is applied on the upper surfaces of a semiconductor chip 152 and a printed circuit board 151 , and the cooling fin 152 is bonded in a sealing manner to the semiconductor chip 152 and the printed circuit board 151 via the adhesive.
  • the cooling fins 100 a and 100 b may be bonded to the semiconductor chip 152 and/or the printed circuit board 151 in a manner such that the cooling fins 100 a and 100 b are machined through a router process depending on the sizes of the semiconductor chip 152 and the printed circuit board 151 , and then the cooling fins are bonded to the semiconductor chip 152 and/or the printed circuit board 151 .
  • “routing” refers to a process of mechanically cutting and/or tailoring the cooling fin 100 a or 100 b using a router bit.
  • the process of mounting the cooling fins 100 a and 100 b on the semiconductor chips 152 which are mounted on the printed circuit boards 151 may be conducted using, for example, an existing chip mounter.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Ceramic Engineering (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Nanotechnology (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Manufacturing & Machinery (AREA)
  • Power Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Computer Hardware Design (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Composite Materials (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Thermal Sciences (AREA)
  • Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
  • Cooling Or The Like Of Electrical Apparatus (AREA)

Abstract

A method of manufacturing a cooling fin and package substrate that includes preparing a mold, which has a support base and a resin layer formed on the support base and including on a side thereof a groove, which is configured to form a cooling fin; printing fireable paste containing a carbon component on a side of the mold that has the groove configured to form a cooling fin; removing the support base to leave a cooling object; and firing the cooling object.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a U.S. divisional application filed under 37 CFR 1.53(b) claiming priority benefit of U.S. Ser. No. 12/219,442 filed in the United States on Jul. 22, 2008 now abandoned, which claims earlier priority benefit to Korean Patent Application No. 10-2008-0051003 filed with the Korean Intellectual Property Office on May 30, 2008, the disclosures of which are incorporated herein by reference.
BACKGROUND
1. Field
The present invention relates generally to a cooling fin and a package substrate comprising the cooling fin and a manufacturing method thereof, and, more particularly, to a cooling fin, which is excellent in cooling performance and is simply manufactured, a package substrate comprising the cooling fin, and a manufacturing method thereof
2. Description of the Related Art
These days, in response to miniaturization and the widening of the functionality of electronic products, more passive/active devices and semiconductor chips (IC) are mounted in the electronic products and packaged. However, as the number of their mounting and packaging are increased, power consumption and heat generation are increased, thus exerting a bad influence on reliability of products and on their attractiveness to customers.
Accordingly, in order to solve the above problems caused by the heat generation, a variety of research on cooling fins is being conducted. Recently, intensive research is being concentrated on a cooling fin incorporating carbon nanotubes (CNT) which have excellent thermal conductivity, i.e., a thermal conductivity ten times or greater than that of copper.
A carbon nanotube is typically produced through chemical vapor deposition (CVD). FIG. 1 shows a carbon nanotube 13, which is produced through chemical vapor deposition.
Referring to FIG. 1, conventional carbon nanotubes 13 are produced in a manner such that nano-sized catalytic metal particles 12 are formed on a silicon substrate 11 and then the carbon nanotubes 13 grow vertically from the catalytic metal particles through a high temperature synthesis process conducted at a temperature ranging from 500° C. to 1000° C. The carbon nanotubes 13 which have been produced in such a manner are attached to a target object so as to serve as cooling fins.
If chemical vapor deposition is used, although it is possible to grow the carbon nanotubes in a vertical direction, it is impossible to enable the carbon nanotubes to have various structures. Thus, there is a limit to the production of cooling fins whose high cooling performance is due to an increase in the surface area of the cooling fins.
Further, since the chemical vapor deposition process must be conducted at a relatively high temperature ranging from 500° C. to 1000° C., the base material from which the carbon nanotubes can be grown is disadvantageously restricted to ones which can be used at the high temperature, for example, the silicon substrate 11, as illustrated in FIG. 1.
Furthermore, the conventional process is disadvantageous in that there are needs for a separate metal catalyst 12 adapted to grow the carbon nanotube as well as a special container having a high hermetic performance regarding forming a nano-sized metal catalyst 12 on the silicon substrate 11, thus increasing equipment costs.
SUMMARY
Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and the present invention provides a cooling fin, which may have various configurations by incorporating a fired object containing carbon component, and a method of manufacturing the cooling fin.
Furthermore, the present invention provides a cooling fin, which may be manufactured a simple process of injecting fireable paste containing carbon nanotubes or carbon nanofiber, and a method of manufacturing the cooling fin.
Furthermore, the present invention provides a package substrate, which may be manufactured by attaching a cooling fin having an improved cooling performance to the package substrate, and a method of manufacturing the package substrate.
Furthermore, the present invention provides a package substrate, which includes a cooling fin that is configured to have a cover structure to improve a cooling performance, and which shields a printed circuit board including a semiconductor chip from an external environment in a sealing manner, thus obviating an additional resin encapsulation, and a method of manufacturing the package substrate.
In one aspect, the present invention provides a cooling fin comprising a fired object containing a carbon component.
The fired object may include carbon nanotubes or carbon nanofibers, and metal microparticles.
In another aspect, the present invention provides a package substrate including: a printed circuit board on which a semiconductor chip is mounted; and a cooling fin bonded to the semiconductor chip and comprising a fired object containing a carbon component.
The fired object may include carbon nanotubes or carbon nanofibers, and metal microparticles.
The cooling fin may be configured to have a cover structure so as to protect a surface of the printed circuit board including the semiconductor chip from an external environment in a sealing manner.
In still another aspect, the present invention provides a method of manufacturing a cooling fin, including: preparing a mold, which comprises a support base and a resin layer formed on the support base and including on a side thereof a groove, which is configured to form a cooling fin; printing fireable paste containing a carbon component on a side of the mold that has the groove configured to form a cooling fin; removing the support base to leave a cooling object; and firing the cooling object.
The preparing the mold may include: placing the resin layer on a side of the support base; imprinting the resin layer with a stamp having a pattern corresponding to the groove; and removing the stamp.
The method may further include, after printing the fireable paste, drying the fireable paste which is printed.
The fireable paste may include carbon nanotubes or carbon nanofibers, metal microparticles and a binder.
The firing the cooling object may cause the resin layer and the binder to be eliminated.
The method may further include, after firing the cooling object, removing the resin layer and the binder which are not eliminated by the firing, through reactive ion etching (RIE).
In a further aspect, the present invention provides a method of manufacturing a package substrate, including: preparing a mold, which comprises a support base and a resin layer formed on the support base and including on a side thereof a groove configured to form a cooling fin; printing fireable paste containing a carbon component on a side of the mold including the groove; removing the support base to leave a cooling object; firing the cooling object to prepare a cooling fin; and bonding the cooling fin on a semiconductor chip mounted on a printed circuit board.
The preparing the mold may include: placing the resin layer on a side of the support base; imprinting the resin layer with a stamp having a pattern corresponding to the groove; and removing the stamp.
The method may further include, after printing the fireable paste, drying the fireable paste which is printed.
The fireable paste may include carbon nanotubes or carbon nanofibers, metal microparticles and a binder.
The firing the cooling object may cause the resin layer and the binder to be eliminated.
The method may further include, after firing the cooling object, removing the resin layer and the binder, which are not eliminated by the firing, through reactive ion etching (RIE).
The cooling fin may be configured to have a cover structure so as to protect a surface of the printed circuit board including the semiconductor chip from an external environment in a sealing manner.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a cross-sectional view showing a carbon nanotube, which is produced through conventional chemical vapor deposition;
FIG. 2 is a cross-sectional view showing a cooling fin according to a preferred embodiment of the present invention;
FIG. 3 is a cross-sectional view showing a package substrate including a cooling fin, according to a preferred embodiment of the present invention;
FIG. 4 is a cross-sectional view showing a package substrate including a cooling fin, according to another embodiment of the present invention; and
FIGS. 5 to 9 are cross-sectional views showing a method of manufacturing a cooling fin, according to an embodiment of the present invention.
 DESCRIPTION OF EMBODIMENTS
Hereinafter, preferred embodiments of the present invention will be described in greater detail with reference to the accompanying drawings.
FIG. 2 is a cross-sectional view showing a cooling fin according to a preferred embodiment of the present invention, FIG. 3 is a cross-sectional view showing a package substrate including a cooling fin, according to a preferred embodiment of the present invention, FIG. 4 is a cross-sectional view showing a package substrate including a cooling fin, according to another embodiment of the present invention, and FIGS. 5 to 7 are cross-sectional views showing a method of manufacturing a cooling fin, according to an embodiment of the present invention.
Referring to FIG. 2, a cooling fin 100 a according to an embodiment of the present invention is now described.
In this embodiment of the present invention, the cooling fin 100 a is distinctively comprised of a fired object containing a carbon component. In this embodiment, the fired object may include carbon nanotubes, carbon nanofibers, metal microparticles and additives.
Here, the carbon nanotubes or the carbon nanofibers have electrical properties superior to other materials. As an example, Table 1 represents the comparison between the physical properties of a carbon nanotube and those of other materials.
TABLE 1
Physical properties carbon nanotube comparative materials
density 1.33~1.40 g/cm3 2.7 g/cm3
current density 1 × 109 A/cm2 1 × 106 A/cm2 (copper cable)
thermal conductivity 6000 W/mK 400 W/mk (copper)
specific resistance 1 × 10−10 · Ω · cm 1 × 10−10 · Ω · cm (copper)
As can be appreciated from Table 1, the carbon nanotube has electrical properties better than metal materials such as aluminum and copper, which are relatively excellent in views of electrical conductivity and specific resistance. Consequently, the cooling fin 100 a, which is comprised of a fired object containing a carbon component, has an excellent cooling performance and is thus capable of efficiently radiating heat generated in a printed circuit board.
Although the carbon nanotubes may be comprised of either or both single-walled carbon nanotubes and multi-walled carbon nanotubes, the multi-walled carbon nanotubes, which have electrical conductivity proportional to a diameter thereof, are used in this embodiment.
The metal microparticles, which function to increase adhesiveness and electrical conductivity, may be comprised of high conductive silver (Ag) microparticles, copper (Cu) microparticles or a proper combination thereof.
The additive, which is an element for controlling adhesiveness and printability, may be comprised of one or more selected from among organic/inorganic filler, dye, pigment, thickener, lubricant agent, defoaming agent, dispersing agent, levelling agent, flame retardant, thixotropic agent, brightener, coupling agent which includes a hydrophobic functional group capable of being coupled to resin in molecules as well as a hydrophilic functional group capable of being coupled to inorganic filler. The inorganic filler, which functions to lower a coefficient of thermal expansion, may include spherical/platy/amorphous silica, alumina, diatomous earth and the like. The additive may include an oxide additive, such as pine tar, to eliminate oxides.
Referring to FIG. 2, although the cooling fin 100 a is shown as being of a specific configuration, for convenience of illustration, it will be apparent that the cooling fin 100 a according to this embodiment of the present invention is not limited to the configuration and may be of various configurations for improvement of cooling performance. As an example thereof, FIG. 4 illustrates a cooling fin 100 b having a cover configuration.
Referring to FIGS. 3 and 4, package substrates 150 a and 150 b, which include cooling fins according to different embodiments of the present invention, are described.
The package substrates 150 a and 150 b, which include cooling fins according to embodiments of the present invention, are characterized in that the cooling fins 100 a and 100 b, which are comprised of fired bodies containing a carbon component, are bonded on respective semiconductor chips 152 which have been mounted on printed circuit boards 152. In this detailed description, as the cooling fins 100 a and 100 b are prepared as described above, the detailed descriptions thereof are omitted for convenience of description.
In this regard, the cooling fins 100 a and 100 b are bonded on the respective semiconductor chips 152 using adhesives 153 etc.
Referring first to FIG. 3, the package substrate 150 a including the cooling fin, according to an embodiment of the present invention is configured such that the cooling fin 100 a is directly bonded on a semiconductor chip 152 using an adhesive 153 to radiate heat generated from the semiconductor chip 152.
Referring then to FIG. 4, the package substrate 150 b including the cooling fin, according to another embodiment of the present invention, is configured such that the cooling fin 100 b is formed into a cover shape for covering an upper surface of a printed circuit board 151 including a semiconductor chip 152 mounted on the printed circuit board 151 in a sealing manner. In practice, the package substrate 150 a including the cooling fin, as shown in FIG. 3, is encapsulated in resin sealing material, such as EMC molding material, so as to protect the semiconductor chip 152 and the printed circuit board 151 from the external environment. Meanwhile, the package substrate 150 b including the cover-shaped cooling fin, as shown in FIG. 4, is designed such that the cooling fin 100 b seals off and shields the semiconductor chip 152 and the printed circuit board 151 from the external environment, thus obviating the necessity of providing an additional resin encapsulation and solving the deterioration of cooling efficiency due to the resin encapsulation. In other words, the adoption of the cover-shaped cooling fin 100 b enables realization of the sealing function as well as of the cooling function.
Referring to FIGS. 3 and 4, although the semiconductor chip 152 is shown mounted on the printed circuit board 151 through a wire bonding technology, it is proposed merely for illustration of an example thereof. Alternatively, the semiconductor chip 152 may be mounted on the printed circuit board 151 through a flip-chip bonding technology, and it is applicable to various kinds of package substrates and memory chips.
A process of manufacturing the cooling fin according to an embodiment of the present invention is described with reference to FIGS. 5 to 9.
As shown in FIG. 5, a resin layer is first formed on one side of a support base 101, and then the resin layer 102 is imprinted with a stamp 103.
In this regard, the support base 101, which is adapted to support the resin layer 102, is preferably constructed to have at least the specific strength required to serve as supporting means. Although the support base 101 may be comprised of a variety of metals and polymers, in particular, releasable polymers, it is comprised of a copper foil in one embodiment.
The resin layer 102, which is in a semicured state, may be formed on one side of the support base 101 in an appropriate way, such as spin coating, droplet dispensing and spraying. In addition, any other process of forming the resin layer 102 on the support base 101 through a known way other than the above-mentioned ways should be understood to fall within the scope of the present invention.
The resin layer 102 may be comprised of any thermosetting resin or thermoplastic resin. More specifically, the resin layer 102 may be comprised of any of the thermosetting resins, such as vinyl ester resin, unsaturated polyester resin, maleimide resin, polycyanate resin, epoxy resin, phenol resin and vinyl benzene compound, and thermoplastic resin, such as polyetherimide resin, polyether sulfone resin and dicylcopentadiene resin.
The stamp 103 is intended to imprint the resin layer 102, which is in a semicured state, with a pattern, thereby defining desired patterned grooves 104 on the resin layer 102 which have been adapted to form the cooling fin. The pattern of the stamp 103 corresponds to the grooves 104 used for forming the cooling fin. The pattern of the stamp may have various shapes suitable for increasing the surface area of the cooling fin, or may have a fine structure suitable for forming the grooves 104 adapted to form a cooling fin having a respective fin thickness of several micrometers.
As shown in FIG. 6, after the imprinting of the resin layer 102, the stamp 103 is removed, thus preparing a mold 105. At this point, by the removal of the stamp 103, the resin layer 102 is provided with the cooling fin-defining grooves 104 which correspond to the pattern of the stamp 103.
Additionally, after the removal of the stamp 103, an operation of drying the semicured resin layer 102 thus permitting the curing of the resin layer to be done.
Subsequently, as shown in FIG. 7, fireable paste 106 containing a carbon component is printed on the one surface of the support base 101 in which the cooling fin-defining grooves 104 are formed.
The fireable paste 106 containing a carbon component is normally comprised of a mixture of binder and powdered carbon nanotubes or carbon nanofibers powder, and may further include metal microparticles, additives and the like.
In this embodiment, the fireable paste 106 may comprise about 75-85 wt % of carbon nanotubes or carbon nanofibers, about 5-10 wt % of binder and about 5 wt % of additive. Herein, since the details of the carbon nanotubes or carbon nanofibers, the metal microparticles and the additive has been previously described above, the description is omitted.
The binder, which is intended to control elasticity and adhesivity of the fireable paste 106, may be used in a varying weight composition depending on need. For example, the binder may include one or more types of thermosetting resin, such as epoxy resin, cyanic acid ester resin, bismaleimide (BMI) resin, polyimide resin, benzocyclobutene (BCB) resin and phenol resin, thermoplastic resin, such as polyurethane resin, polyamideimide resin and polyphenylene ether resin, and UV curing resin. Furthermore, binder may be selected from the group consisting of polyethylene oxide, polypropylene carbonate and a combination thereof. This allows firing at a low temperature and easy decomposition of the binder during the firing process, thus preventing deterioration of the carbon nanotubes or carbon nanofibers and improving thermal conductivity.
As shown in FIG. 8, the support base 101 is removed to leave a cooling object 107.
In an embodiment, when the support base 101 is embodied as a copper foil, the support base 101 may be removed using etching solution such as iron chloride (FeCl5) etchant, copper chloride (CuCl5), alkali etchant and hydrogen peroxide/sulfuric acid (H2O2/H2SO4). At this time, the fireable paste 106 is not etched even by the etching solution.
As shown in FIG. 9, the cooling object 107 is subjected to a firing process so as to eliminate the binder and the resin layer 102, thus preparing the cooling fin 100 a as illustrated in FIG. 2.
At this point, as the fireable paste 106 is heated to a temperature of 500° C. or higher during the firing process, the binder contained in the paste binds the carbon nanotubes or carbon nanofibers to each other and is then thermally decomposed and thus eliminated. Further, since the resin layer 102 included in the cooling object 107 is also thermally decomposed at a temperature of 300° C. or higher, it is eliminated after the firing process. As a result, the cooling fin 100 a is comprised of a fired object containing carbon nanotubes or carbon nanofibers, metal microparticles and an additive.
Meanwhile, since the cover-shaped cooling fin 100 b, as shown in FIG. 4, is also manufactured through a process which is substantially identical to the above process used in the manufacture of the cooling fin 100 a, the description thereof is omitted.
When the binder and the resin layer still remain even after the firing process, a process may be further conducted such that the binder and the resin layer are eliminated using reactive ion etching (RIE) technology for improvement of the cooling performance. The reactive ion etching technology is conducted in such a manner as to react active species existing in a plasma of reactive gas with atoms on the surface of an etching target material to generate volatile reaction products, and then separate the volatile reaction products from the surface of the etching target material. In this embodiment of the present invention, the reactive ion etching may be conducted through a dielectric barrier discharge (DBD) using inert gases such as argon (Ar) or helium (He).
The package substrates 105 a and 150 b, each including the cooling fin, according to an embodiment of the present invention, is manufactured by bonding the cooling fins 100 a and 100 b, which have been prepared in the above-described way, to respective printed circuit boards 151 on which semiconductor chips 152 are mounted. The process of manufacturing the package substrates is now described with reference to FIGS. 3 and 4.
In a process of manufacturing the package substrate 150 a according to an embodiment of the present invention, as shown in FIG. 3, an adhesive 153 is applied onto a semiconductor chip 152 mounted on a printed circuit board 151, and the cooling fin 100 a, which has been prepared through the process as shown in FIGS. 5 to 9, is bonded to the semiconductor chip 152 via the adhesive 153.
In a process of manufacturing the package substrate 105 b according to another embodiment of the present invention, as shown in FIG. 4, an adhesive is applied on the upper surfaces of a semiconductor chip 152 and a printed circuit board 151, and the cooling fin 152 is bonded in a sealing manner to the semiconductor chip 152 and the printed circuit board 151 via the adhesive.
In the processes, the cooling fins 100 a and 100 b may be bonded to the semiconductor chip 152 and/or the printed circuit board 151 in a manner such that the cooling fins 100 a and 100 b are machined through a router process depending on the sizes of the semiconductor chip 152 and the printed circuit board 151, and then the cooling fins are bonded to the semiconductor chip 152 and/or the printed circuit board 151. In this process, “routing” refers to a process of mechanically cutting and/or tailoring the cooling fin 100 a or 100 b using a router bit.
Alternatively, the process of mounting the cooling fins 100 a and 100 b on the semiconductor chips 152 which are mounted on the printed circuit boards 151 may be conducted using, for example, an existing chip mounter.
Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. Accordingly, the modifications, additions and substitutions should also be understood to fall within the scope of the present invention.

Claims (13)

1. A method of manufacturing a cooling fin, comprising:
preparing a mold, which comprises a support base and a resin layer formed on the support base and including on a side thereof a groove, which is configured to form a cooling fin;
printing fireable paste containing a carbon component on a side of the mold that has the groove configured to form a cooling fin;
removing the support base to leave a cooling object; and
firing the cooling object.
2. The method according to claim 1, wherein preparing the mold comprises:
forming the resin layer on a side of the support base;
imprinting the resin layer with a stamp having a pattern corresponding to the groove; and
removing the stamp.
3. The method according to claim 1, further comprising, after printing the fireable paste, drying the fireable paste which is printed.
4. The method according to claim 1, wherein the fireable paste includes carbon nanotubes or carbon nanofibers, metal microparticles and a binder.
5. The method according to claim 4, wherein firing the cooling object causes the resin layer and the binder to be eliminated.
6. The method according to claim 5, further comprising, after firing the cooling object,
removing the resin layer and the binder which are not eliminated by the firing, through reactive ion etching (RIE).
7. A method of manufacturing a package substrate, comprising:
preparing a mold, which comprises a support base and a resin layer formed on the support base and including on a side thereof a groove configured to form a cooling fin;
printing fireable paste containing a carbon component on a side of the mold including the groove;
removing the support base to leave a cooling object;
firing the cooling object to prepare a cooling fin; and
bonding the cooling fin on a semiconductor chip mounted on a printed circuit board.
8. The method according to claim 7, wherein the preparing the mold comprises:
placing the resin layer on a side of the support base;
imprinting the resin layer with a stamp having a pattern corresponding to the groove; and
removing the stamp.
9. The method according to claim 7, further comprising, after printing the fireable paste, drying the fireable paste which is printed.
10. The method according to claim 7, wherein the fireable paste includes carbon nanotubes or carbon nanofibers, metal microparticles and a binder.
11. The method according to claim 10, wherein firing the cooling object causes the resin layer and the binder to be eliminated.
12. The method according to claim 11, further comprising, after firing the cooling object,
removing the resin layer and the binder, which are not eliminated by the firing, through reactive ion etching (RIE).
13. The method according to claim 7, wherein the cooling fin is configured to have a cover structure so as to protect a surface of the printed circuit board including the semiconductor chip from an external environment in a sealing manner.
US13/137,669 2008-05-30 2011-09-01 Method of manufacturing cooling fin and package substrate with cooling fin Expired - Fee Related US8377748B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US13/137,669 US8377748B2 (en) 2008-05-30 2011-09-01 Method of manufacturing cooling fin and package substrate with cooling fin

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
KR10-2008-0051003 2008-05-30
KR1020080051003A KR101022954B1 (en) 2008-05-30 2008-05-30 Cooling fin and package substrate comprising the cooling fin and fabricating method of the same
US12/219,442 US20090294956A1 (en) 2008-05-30 2008-07-22 Cooling fin and package substrate comprising the cooling fin and manufacturing method thereof
US13/137,669 US8377748B2 (en) 2008-05-30 2011-09-01 Method of manufacturing cooling fin and package substrate with cooling fin

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US12/219,442 Division US20090294956A1 (en) 2008-05-30 2008-07-22 Cooling fin and package substrate comprising the cooling fin and manufacturing method thereof

Publications (2)

Publication Number Publication Date
US20110308069A1 US20110308069A1 (en) 2011-12-22
US8377748B2 true US8377748B2 (en) 2013-02-19

Family

ID=41378769

Family Applications (2)

Application Number Title Priority Date Filing Date
US12/219,442 Abandoned US20090294956A1 (en) 2008-05-30 2008-07-22 Cooling fin and package substrate comprising the cooling fin and manufacturing method thereof
US13/137,669 Expired - Fee Related US8377748B2 (en) 2008-05-30 2011-09-01 Method of manufacturing cooling fin and package substrate with cooling fin

Family Applications Before (1)

Application Number Title Priority Date Filing Date
US12/219,442 Abandoned US20090294956A1 (en) 2008-05-30 2008-07-22 Cooling fin and package substrate comprising the cooling fin and manufacturing method thereof

Country Status (3)

Country Link
US (2) US20090294956A1 (en)
JP (1) JP4918075B2 (en)
KR (1) KR101022954B1 (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8537553B2 (en) * 2011-02-14 2013-09-17 Futurewei Technologies, Inc. Devices having anisotropic conductivity heatsinks, and methods of making thereof
JP6118540B2 (en) * 2012-11-08 2017-04-19 新光電気工業株式会社 Heat dissipation component and manufacturing method thereof
CN103001882A (en) * 2012-11-29 2013-03-27 四川高软软件科技有限公司 Wideband edge protection router
CN106098654B (en) * 2016-06-20 2018-12-14 绍兴杭铭饰品有限公司 A kind of integrated antenna package of optimizing thermal solution
TW201821585A (en) * 2016-11-30 2018-06-16 國立成功大學 High efficiency thermal conductivity structure
KR102271150B1 (en) * 2017-03-14 2021-07-01 엘지이노텍 주식회사 Heat sink and thermo electric element having the same
KR102032419B1 (en) * 2019-03-11 2019-10-15 주식회사 제이케이테크원 Copper based metal PCB

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002110874A (en) 2000-09-29 2002-04-12 Edl:Kk Heat sink and its producing method
JP2004207690A (en) 2002-12-13 2004-07-22 Usui Kokusai Sangyo Kaisha Ltd Heat sink made of resin material
JP2004349685A (en) 2003-04-14 2004-12-09 Integral Technologies Inc Low-cost thermal management device or heat sink manufactured from conductive filler-loaded resin-based material
US20060057768A1 (en) * 2002-12-09 2006-03-16 Kabushiki Kaisha Toyota Chuo Kenkyusho Semiconductor element heat dissipating member, semiconductor device using same and manufacturing same
JP2007169446A (en) 2005-12-21 2007-07-05 Sekisui Chem Co Ltd Acrylic resin composition and paste composition
US20080174963A1 (en) * 2007-01-24 2008-07-24 Foxconn Technology Co., Ltd. Heat spreader with vapor chamber defined therein
US20080230894A1 (en) * 2007-03-21 2008-09-25 Sun Microsystems, Inc. Carbon nanotubes for active direct and indirect cooling of electronics device

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0541471A (en) * 1991-08-07 1993-02-19 Hitachi Ltd Semiconductor integrated circuit device
JPH09162338A (en) * 1995-12-07 1997-06-20 Janome Sewing Mach Co Ltd Lsi heat sink and manufacture thereof
JP3818102B2 (en) 2001-08-31 2006-09-06 住友電気工業株式会社 Heat dissipation substrate, method for manufacturing the same, and semiconductor device
US20050116336A1 (en) 2003-09-16 2005-06-02 Koila, Inc. Nano-composite materials for thermal management applications

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002110874A (en) 2000-09-29 2002-04-12 Edl:Kk Heat sink and its producing method
US20060057768A1 (en) * 2002-12-09 2006-03-16 Kabushiki Kaisha Toyota Chuo Kenkyusho Semiconductor element heat dissipating member, semiconductor device using same and manufacturing same
JP2004207690A (en) 2002-12-13 2004-07-22 Usui Kokusai Sangyo Kaisha Ltd Heat sink made of resin material
JP2004349685A (en) 2003-04-14 2004-12-09 Integral Technologies Inc Low-cost thermal management device or heat sink manufactured from conductive filler-loaded resin-based material
JP2007169446A (en) 2005-12-21 2007-07-05 Sekisui Chem Co Ltd Acrylic resin composition and paste composition
US20080174963A1 (en) * 2007-01-24 2008-07-24 Foxconn Technology Co., Ltd. Heat spreader with vapor chamber defined therein
US20080230894A1 (en) * 2007-03-21 2008-09-25 Sun Microsystems, Inc. Carbon nanotubes for active direct and indirect cooling of electronics device

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
Japanese Office Action issued on May 31, 2011 in corresponding Japanese Patent Application No. 2008-211566.
Korean Office Action issued Apr. 30, 2010 in corresponding Korean Patent Application No. 10-2008-0051003.
U.S. Appl. No. 12/219,442, filed Jul. 22, 2008, Eung Suek Lee et al., Samsung Electro-Mechanics Co., Ltd.
U.S. Patent Final Office Action mailed May 9, 2011 in corresponding U.S. Appl. No. 12/219,442.
U.S. Patent Office Action mailed Nov. 24, 2010 in corresponding U.S. Appl. No. 12/219,442.
U.S. Patent Restriction Requirement mailed Sep. 16, 2010 in corresponding U.S. Appl. No. 12/219,442.

Also Published As

Publication number Publication date
KR101022954B1 (en) 2011-03-16
KR20090124662A (en) 2009-12-03
JP4918075B2 (en) 2012-04-18
US20110308069A1 (en) 2011-12-22
US20090294956A1 (en) 2009-12-03
JP2009290185A (en) 2009-12-10

Similar Documents

Publication Publication Date Title
US8377748B2 (en) Method of manufacturing cooling fin and package substrate with cooling fin
US20090072013A1 (en) Nano-scale particle paste for wiring microelectronic devices using ink-jet printing
EP1810332B1 (en) Nanotube-based circuit connection approach
CN107771354B (en) Engineering polymer electronic material
US9307676B2 (en) Thermally enhanced electronic package
CN102822962B (en) Plug-in part and employ the electronic installation of this plug-in part
US8461462B2 (en) Circuit substrate, laminated board and laminated sheet
US20120118615A1 (en) Metal clad laminate, method of manufacturing the same, and heat-radiating substrate
CN106537570A (en) Printed interconnects for semiconductor packages
US10985085B2 (en) Semiconductor device package and method for manufacturing the same
US20120189818A1 (en) Structure and method for manufacturing the same
US8300420B2 (en) Circuit substrate for mounting electronic component and circuit substrate assembly having same
US7834467B2 (en) Layer between interfaces of different components in semiconductor devices
US6085415A (en) Methods to produce insulated conductive through-features in core materials for electric packaging
KR20090124816A (en) Conductive paste including a carbon nanotube and printed circuit board using the same
US11521918B2 (en) Semiconductor device having component mounted on connection bar and lead on top side of lead frame and method of manufacturing semiconductor device thereof
US20100051331A1 (en) Circuit substrate for mounting electronic component and circuit substrate assembly having same
US7714451B2 (en) Semiconductor package system with thermal die bonding
US20200388552A1 (en) Semiconductor package carrier board, method for fabricating the same, and electronic package having the same
US11183447B2 (en) Flip-chip package substrate and method for fabricating the same
US7504711B2 (en) Semiconductor substrate with strip conductors formed of carbon nanotubes and production thereof
JP5695780B1 (en) High thermal conductivity / electrical insulation / low thermal expansion powder, heat dissipation structure using the same, and method for producing the powder
US11450597B2 (en) Semiconductor package substrate having heat dissipating metal sheet on solder pads, method for fabricating the same, and electronic package having the same
JP3231295B2 (en) Metal base circuit board
KR101205866B1 (en) Manufacturing method of metal pcb and metal pcb thereof

Legal Events

Date Code Title Description
FEPP Fee payment procedure

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

REMI Maintenance fee reminder mailed
LAPS Lapse for failure to pay maintenance fees
STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

FP Lapsed due to failure to pay maintenance fee

Effective date: 20170219